Teenage aggression linked to faster biological aging and health risks later in life

Teens who frequently lash out at others may face lasting physical health consequences later in life, according to research published by the American Psychological Association. The study found that aggressive behavior in early adolescence is linked to faster biological aging and higher body mass index (BMI) by age 30.

This study highlights the potential lasting health consequences stemming from social challenges that emerge in early adolescence. Accelerated aging has been linked to an increased risk for future coronary artery disease, diabetes, high blood pressure, inflammation and even early death."

Joseph Allen, PhD, lead author, University of Virginia

The study, published in the journal Health Psychology, followed 121 middle school students (46 male and 75 female) from suburban and urban communities in the Southeastern United States.

Researchers tracked participants from age 13 into adulthood, collecting self-reports of aggression, parent reports of family conflict, and peer reports of relationship behavior. When participants reached age 30, researchers assessed biological aging using blood-based biomarkers.

"There were 12 markers in all, which included C-reactive protein, blood sugar, white blood cell count, etc. We then used a recently developed algorithm that combines all of these and yields an estimate of a person's biological age, which turns out to be a better predictor of their health and eventual mortality than their actual chronological age," said Allen.

Biological aging was measured using two validated methods: the Klemera-Doubal approach and PhenoAge. Both methods combine indicators such as blood pressure, inflammation, glucose, cholesterol and immune function to estimate how old a person's body appears compared with their actual age.

"Both methods showed that higher levels of aggression in early adolescence predicted more advanced biological age by 30, even after accounting for gender, family income, serious childhood illness and adolescent body shape," said Allen.

Interestingly, researchers also found that males and individuals from lower-income families showed signs of faster biological aging. Further analysis suggested these patterns were tied to relationship difficulties. Boys experienced more conflict with their fathers, while teens from lower-income families were more likely to show punitive behavior toward peers.

Worth noting is that early aggression alone did not predict faster aging unless it led to ongoing relationship problems later in life, according to Allen. Teens who showed higher levels of aggression were more likely to argue with parents and mistreat friends as they grew older. Those continued relationship struggles-not early aggression by itself-were what ultimately predicted accelerated aging.

"This study does not prove that teenage aggression directly causes faster aging," Allen said. "Other factors we didn't measure may also be playing a role, and it's likely that what really matters is how those early behaviors turn into later relationship problems. We also can't yet say whether it's aggressive actions, hostile attitudes or a mix of both that makes the difference."

Still, the findings suggest that early relationship problems may serve as warning signs for long-term health risks, according to Allen. They also highlight the importance of helping adolescents develop healthier relationships early in life, efforts that could benefit both mental and physical health well into adulthood.

"Adolescents are often mocked for treating their relationships as matters of life and death," Allen said. "These findings suggest that, in some ways, they are really on to something, which is that relationships beginning in adolescence, and especially patterns of conflict and aggression that begin in adolescence, do seem to have long-term fundamental physical health implications."